Organophosphate ester flame retardants and plasticizers in house dust and Child Behavior Checklist outcomes: A nested study in the Canadian CHILD Birth Cohort

Stephanie A Foster; Molly L Kile; Perry Hystad; Miriam L Diamond; Piush J Mandhane; Theo J Moraes; Jacqueline Pei; James A Scott; Elinor Simons; Padmaja Subbarao; Tim K Takaro; Sukhpreet K Tamana; Stuart E Turvey; Jeffrey R Brook

doi:10.1038/s41370-025-00821-y

Organophosphate ester flame retardants and plasticizers in house dust and Child Behavior Checklist outcomes: A nested study in the Canadian CHILD Birth Cohort

J Expo Sci Environ Epidemiol. 2026 Mar;36(2):322-333. doi: 10.1038/s41370-025-00821-y. Epub 2025 Nov 8.

Authors

Stephanie A Foster¹, Molly L Kile², Perry Hystad², Miriam L Diamond^{3

4}, Piush J Mandhane^{5

6}, Theo J Moraes⁷, Jacqueline Pei⁵, James A Scott⁸, Elinor Simons⁹, Padmaja Subbarao^{7

8}, Tim K Takaro¹⁰, Sukhpreet K Tamana¹¹, Stuart E Turvey¹¹, Jeffrey R Brook⁸

Affiliations

¹ School of Nutrition and Public Health, College of Health, Oregon State University, 160 SW 26th St, Corvallis, OR, 97331, USA. Fosters2@oregonstate.edu.
² School of Nutrition and Public Health, College of Health, Oregon State University, 160 SW 26th St, Corvallis, OR, 97331, USA.
³ Department of Earth Sciences, University of Toronto, 22 Ursula Franklin Street, Toronto, ON, M5S 3B1, Canada.
⁴ School of the Environment, University of Toronto, 33 Willcocks Street, Suite 1016V, Toronto, ON, M5S 3E8, Canada.
⁵ Pediatric Respiratory Medicine, University of Alberta, 11405-87 Avenue Edmonton, Alberta, T6G 1C9, Canada.
⁶ Faculty of Medicine & Health Sciences, UCSI University, 1 Jalan UCSI, UCSI Heights (Taman Connaught), Cheras, 56000, Kuala Lumpur, Malaysia.
⁷ Department of Pediatrics, University of Toronto, 555 University Avenue, Black Wing Room 1436, Toronto, ON, M5G 1×8, Canada.
⁸ Dalla Lana School of Public Health, University of Toronto, 155 College Street, Sixth Floor, Toronto, ON, MST 3M7, Canada.
⁹ Department of Pediatrics and Child Health, University of Manitoba, 840 Sherbrook Street, University of Manitoba, Winnipeg, MB, R3A 1S1, Canada.
¹⁰ Department of Health Sciences, Simon Fraser University, 8888 University Drive, Blusson Hall, Room 11300, Burnaby, B.C, V5A 1S6, Canada.
¹¹ Pediatric Immunology, The University of British Columbia, 2329 West Mall, Vancouver, BC, V6T 1Z4, Canada.

Abstract

Background: Organophosphate esters and plasticizers (OPEs) are used in consumer materials to meet flammability standards. Toxicological and epidemiological evidence suggests some OPEs are developmental neurotoxicants.

Objective: We investigated associations between OPE exposures as measured in house dust and emotional and behavioral problems in young children.

Methods: We used data from the CHILD Cohort Study (n = 601), a prospective birth cohort recruited in 5 cities across Canada (2008-2012). OPEs were measured in house dust at 3-4 months postpartum, and parents completed the Child Behavior Checklist (CBCL), which measures emotional and behavioral problems when their child was 5 years. We used logistic regression to examine associations between OPE Z-scores (individual and summed chlorinated [ΣOPE_Cl] and non-chlorinated [ΣOPE_NCl]) and CBCL problem scale scores (borderline and clinical T-scores ≥60 and normal <60).

Results: Tris(2-chloroethyl) phosphate (TCEP) showed strong, positive associations with CBCL Total and Externalizing scores at or above the clinical cutoff, meaning children with higher levels of TCEP in house dust postpartum had higher odds of developing clinically relevant behavioral problems in early childhood compared to children with lower levels (Total OR_adj: 1.37, 95% CI: 1.01, 1.87; Externalizing OR_adj: 1.36, 95% CI: 1.00, 1.85). Similarly, 4-isopropylphenyl diphenyl phosphate, a Firemaster 550 component, had a strong, positive association with Internalizing scores (OR_adj: 1.24, 95% CI: 1.02, 1.51). We observed a weak association between ΣOPE_Cl and Total scores (Odds Ratio [OR] adjusted: 1.14, 95% Confidence Intervals [CI]: 0.97, 1.33) and null associations for ΣOPE_NCl. Associations were generally stronger among boys (ΣOPE_Cl Total OR_adj: 1.31, 95% CI: 1.02, 1.68). Visual summary of this manuscript, created with Microsoft PowerPoint.

Impact: Organophosphate esters (OPEs) are common aspects of our built environment and increasingly recognized as developmental neurotoxicants. Using data from a large Canadian birth cohort, we investigated associations between OPE exposures as measured in house dust postpartum and emotional and behavioral problems in children. We found that levels of two OPE compounds (tris(2-chloroethyl) phosphate and a component of Firemaster 550) were associated with increased odds of clinically relevant behavioral problems in early childhood. This important work underscores the urgent need for public health policies to limit the use of certain OPEs in consumer products to reduce children's exposure to harmful chemicals.

Keywords: Children’s health; Early life exposure; Epidemiology; Flame retardants; Indoor dust/house dust/dust; Neurodevelopment.

MeSH terms

Birth Cohort
Canada / epidemiology
Child Behavior* / drug effects
Child, Preschool
Dust* / analysis
Environmental Exposure* / adverse effects
Environmental Exposure* / analysis
Esters
Female
Flame Retardants* / analysis
Flame Retardants* / toxicity
Humans
Infant
Male
Organophosphates* / analysis
Organophosphates* / toxicity
Plasticizers* / analysis
Plasticizers* / toxicity
Prospective Studies

Substances

Dust
Flame Retardants
Plasticizers
Organophosphates
Esters

Abstract

MeSH terms

Substances

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